Remove redundant fake facade classes

Fixed #KT-35122 #EA-218642 #EA-217640

compiler/light-classes/src/org/jetbrains/kotlin/asJava/LightClassUtil.kt

@@ -173,7 +173,6 @@ object LightClassUtil {
         val classesWithMatchingFqName = JavaElementFinder.getInstance(project).findClasses(fqName.asString(), GlobalSearchScope.allScope(project))
         return classesWithMatchingFqName.singleOrNull() ?:
                classesWithMatchingFqName.find {
-                   // NOTE: for multipart facades this works via FakeLightClassForFileOfPackage
                    it.containingFile?.virtualFile == ktFile.virtualFile
                }
     }

compiler/light-classes/src/org/jetbrains/kotlin/asJava/classes/FakeLightClassForFileOfPackage.java

@@ -1,123 +0,0 @@
-/*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.kotlin.asJava.classes;
-
-import com.intellij.lang.Language;
-import com.intellij.psi.PsiClass;
-import com.intellij.psi.PsiElement;
-import com.intellij.psi.PsiFile;
-import com.intellij.psi.impl.light.AbstractLightClass;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-import org.jetbrains.kotlin.asJava.elements.KtLightAbstractAnnotation;
-import org.jetbrains.kotlin.asJava.finder.JavaElementFinder;
-import org.jetbrains.kotlin.idea.KotlinLanguage;
-import org.jetbrains.kotlin.load.java.structure.LightClassOriginKind;
-import org.jetbrains.kotlin.psi.KtClassOrObject;
-import org.jetbrains.kotlin.psi.KtFile;
-
-import java.util.List;
-
-/**
- * This class serves as a workaround for usages of {@link JavaElementFinder#findClasses} which eventually only need names of files
- * containing the class. When queried for a package class (e.g. test/TestPackage), {@code findClasses} along with a
- * {@link KtLightClassForFacade} would also return multiple instances of this class for each file present in the package. The client
- * code can make use of every file in the package then, since {@code getContainingFile} of these instances will represent the whole package.
- * <p/>
- * See {@link LineBreakpoint#findClassCandidatesInSourceContent} for the primary usage this was introduced
- */
-public class FakeLightClassForFileOfPackage extends AbstractLightClass implements KtLightClass {
-    private final KtLightClassForFacade delegate;
-    private final KtFile file;
-
-    public FakeLightClassForFileOfPackage(@NotNull KtLightClassForFacade delegate, @NotNull KtFile file) {
-        super(delegate.getManager());
-        this.delegate = delegate;
-        this.file = file;
-    }
-
-    @NotNull
-    @Override
-    public PsiClass getClsDelegate() {
-        return delegate;
-    }
-
-    @Nullable
-    @Override
-    public KtClassOrObject getKotlinOrigin() {
-        return null;
-    }
-
-    @Override
-    public PsiFile getContainingFile() {
-        return file;
-    }
-
-    @Override
-    public boolean isValid() {
-        // This is intentionally false to prevent using this as a real class
-        return false;
-    }
-
-    @NotNull
-    @Override
-    public PsiClass getDelegate() {
-        return delegate;
-    }
-
-    @NotNull
-    @Override
-    public PsiElement copy() {
-        return new FakeLightClassForFileOfPackage(delegate, file);
-    }
-
-    @Override
-    public String getText() {
-        return null;
-    }
-
-    @NotNull
-    @Override
-    public Language getLanguage() {
-        return KotlinLanguage.INSTANCE;
-    }
-
-    @Override
-    public boolean equals(Object obj) {
-        if (!(obj instanceof FakeLightClassForFileOfPackage)) return false;
-
-        FakeLightClassForFileOfPackage other = (FakeLightClassForFileOfPackage) obj;
-        return file == other.file && delegate.equals(other.delegate);
-    }
-
-    @Override
-    public int hashCode() {
-        return file.hashCode() * 31 + delegate.hashCode();
-    }
-
-    @NotNull
-    @Override
-    public LightClassOriginKind getOriginKind() {
-        return LightClassOriginKind.SOURCE;
-    }
-
-    @Nullable
-    @Override
-    public List<KtLightAbstractAnnotation> getGivenAnnotations() {
-        return null;
-    }
-}

compiler/light-classes/src/org/jetbrains/kotlin/asJava/finder/JavaElementFinder.kt

@@ -21,12 +21,12 @@ import com.intellij.openapi.extensions.Extensions
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.util.Condition
 import com.intellij.psi.*
+import com.intellij.psi.impl.compiled.ClsClassImpl
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.util.PsiUtilCore
 import com.intellij.util.SmartList
 import com.intellij.util.containers.ContainerUtil
 import org.jetbrains.kotlin.asJava.KotlinAsJavaSupport
-import org.jetbrains.kotlin.asJava.classes.FakeLightClassForFileOfPackage
 import org.jetbrains.kotlin.asJava.toLightClass
 import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.name.FqName
@@ -58,7 +58,9 @@ class JavaElementFinder(
         answer.addAll(kotlinAsJavaSupport.getFacadeClasses(qualifiedName, scope))
         answer.addAll(kotlinAsJavaSupport.getKotlinInternalClasses(qualifiedName, scope))
 
-        return answer.sortByClasspathPreferringNonFakeFiles(scope).toTypedArray()
+        sortByPreferenceToSourceFile(answer, scope)
+
+        return answer.toTypedArray()
     }
 
     // Finds explicitly declared classes and objects, not package classes
@@ -141,15 +143,22 @@ class JavaElementFinder(
             answer.add(aClass)
         }
 
-        return answer.sortByClasspathPreferringNonFakeFiles(scope).toTypedArray()
+        sortByPreferenceToSourceFile(answer, scope)
+
+        return answer.toTypedArray()
     }
 
-    override fun getPackageFiles(psiPackage: PsiPackage, scope: GlobalSearchScope): Array<PsiFile> {
+    private fun sortByPreferenceToSourceFile(list: SmartList<PsiClass>, searchScope: GlobalSearchScope) {
-        val packageFQN = FqName(psiPackage.qualifiedName)
+        if (list.size < 2) return
-        // TODO: this does not take into account JvmPackageName annotation
+        // NOTE: this comparator might violate the contract depending on the scope passed
-        return kotlinAsJavaSupport.findFilesForPackage(packageFQN, scope).toTypedArray()
+        ContainerUtil.quickSort(list, byClasspathComparator(searchScope))
+        list.sortBy { it !is ClsClassImpl }
     }
 
+    // TODO: this does not take into account JvmPackageName annotation
+    override fun getPackageFiles(psiPackage: PsiPackage, scope: GlobalSearchScope): Array<PsiFile> =
+        kotlinAsJavaSupport.findFilesForPackage(FqName(psiPackage.qualifiedName), scope).toTypedArray()
+
     override fun getPackageFilesFilter(psiPackage: PsiPackage, scope: GlobalSearchScope): Condition<PsiFile>? {
         return Condition { input ->
             if (input !is KtFile) {
@@ -184,15 +193,5 @@ class JavaElementFinder(
                 }
             }
         }
-
-        private fun List<PsiClass>.sortByClasspathPreferringNonFakeFiles(searchScope: GlobalSearchScope): List<PsiClass> {
-            val result = this.toMutableList()
-            // NOTE: this comparator might violate the contract depending on the scope passed
-            ContainerUtil.quickSort(result, byClasspathComparator(searchScope))
-            result.sortBy {
-                it is FakeLightClassForFileOfPackage
-            }
-            return result
-        }
     }
 }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/project/getModuleInfo.kt

@@ -15,7 +15,6 @@ import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiFile
 import org.jetbrains.kotlin.analyzer.ModuleInfo
-import org.jetbrains.kotlin.asJava.classes.FakeLightClassForFileOfPackage
 import org.jetbrains.kotlin.asJava.classes.KtLightClassForFacade
 import org.jetbrains.kotlin.asJava.elements.KtLightElement
 import org.jetbrains.kotlin.caches.project.cacheInvalidatingOnRootModifications
@@ -214,7 +213,6 @@ private fun <T> KtLightElement<*, *>.processLightElement(c: ModuleInfoCollector<
     }
 
     val element = kotlinOrigin ?: when (this) {
-        is FakeLightClassForFileOfPackage -> this.getContainingFile()!!
         is KtLightClassForFacade -> this.files.first()
         else -> return c.onFailure("Light element without origin is referenced by resolve:\n$this\n${this.clsDelegate.text}")
     }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/IDEKotlinAsJavaSupport.kt

@@ -12,6 +12,7 @@ import com.intellij.psi.impl.compiled.ClsClassImpl
 import com.intellij.psi.impl.compiled.ClsFileImpl
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.util.PsiTreeUtil
+import com.intellij.util.SmartList
 import org.jetbrains.kotlin.asJava.KotlinAsJavaSupport
 import org.jetbrains.kotlin.asJava.builder.ClsWrapperStubPsiFactory
 import org.jetbrains.kotlin.asJava.classes.*
@@ -34,7 +35,6 @@ import org.jetbrains.kotlin.platform.jvm.isJvm
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.resolve.scopes.MemberScope
 import org.jetbrains.kotlin.utils.sure
-import java.util.*
 
 class IDEKotlinAsJavaSupport(private val project: Project) : KotlinAsJavaSupport() {
     private val psiManager: PsiManager = PsiManager.getInstance(project)
@@ -151,19 +151,6 @@ class IDEKotlinAsJavaSupport(private val project: Project) : KotlinAsJavaSupport
         return KtLightClassForScript.create(script)
     }
 
-    private fun withFakeLightClasses(
-        lightClassForFacade: KtLightClassForFacade
-    ): List<PsiClass> {
-        val lightClasses = ArrayList<PsiClass>()
-        lightClasses.add(lightClassForFacade)
-        if (lightClassForFacade.files.size > 1) {
-            lightClasses.addAll(lightClassForFacade.files.map {
-                FakeLightClassForFileOfPackage(lightClassForFacade, it)
-            })
-        }
-        return lightClasses
-    }
-
     override fun getFacadeClasses(facadeFqName: FqName, scope: GlobalSearchScope): Collection<PsiClass> {
         val filesByModule = findFilesForFacade(facadeFqName, scope).groupBy(PsiElement::getModuleInfoPreferringJvmPlatform)
 
@@ -215,24 +202,20 @@ class IDEKotlinAsJavaSupport(private val project: Project) : KotlinAsJavaSupport
         facadeFqName: FqName,
         facadeFiles: List<KtFile>,
         moduleInfo: IdeaModuleInfo
-    ): List<PsiClass> {
+    ): List<PsiClass> = SmartList<PsiClass>().apply {
-        val (clsFiles, _) = facadeFiles.partition { it is KtClsFile }
+
-        val facadesFromCls = clsFiles.mapNotNull { createLightClassForDecompiledKotlinFile(it as KtClsFile) }
+        tryCreateFacadesForSourceFiles(moduleInfo, facadeFqName)?.let { sourcesFacade ->
-        val facadesFromSources = createFacadesForSourceFiles(moduleInfo, facadeFqName)
+            add(sourcesFacade)
-        return facadesFromSources + facadesFromCls
+        }
+
+        facadeFiles.filterIsInstance<KtClsFile>().mapNotNullTo(this) {
+            createLightClassForDecompiledKotlinFile(it)
+        }
     }
 
-    private fun createFacadesForSourceFiles(
+    private fun tryCreateFacadesForSourceFiles(moduleInfo: IdeaModuleInfo, facadeFqName: FqName): PsiClass? {
-        moduleInfo: IdeaModuleInfo,
+        if (moduleInfo !is ModuleSourceInfo && moduleInfo !is PlatformModuleInfo) return null
-        facadeFqName: FqName
+        return KtLightClassForFacade.createForFacade(psiManager, facadeFqName, moduleInfo.contentScope())
-    ): List<PsiClass> {
-        if (moduleInfo !is ModuleSourceInfo && moduleInfo !is PlatformModuleInfo) return listOf()
-
-        val lightClassForFacade = KtLightClassForFacade.createForFacade(
-            psiManager, facadeFqName, moduleInfo.contentScope()
-        )
-
-        return if (lightClassForFacade !== null) withFakeLightClasses(lightClassForFacade) else emptyList()
     }
 
     override fun findFilesForFacade(facadeFqName: FqName, scope: GlobalSearchScope): Collection<KtFile> {

idea/tests/org/jetbrains/kotlin/asJava/LightClassesClasspathSortingTest.kt

@@ -46,7 +46,6 @@ class LightClassesClasspathSortingTest : KotlinLightCodeInsightFixtureTestCase()
         val psiClass = JavaPsiFacade.getInstance(project).findClass(fqName, ResolveScopeManager.getElementResolveScope(file))
 
         assertNotNull(psiClass, "Can't find class for $fqName")
-        psiClass!!
         assert(psiClass is KtLightClassForSourceDeclaration || psiClass is KtLightClassForFacade) { "Should be an explicit light class, but was $fqName ${psiClass::class.java}" }
         assert(psiClass !is KtLightClassForDecompiledDeclaration) { "Should not be decompiled light class: $fqName ${psiClass::class.java}" }
     }